Shinichi Ishida

SoR-Based Programmable Network for Future Software-Defined Network

The Future Internet architecture would be advanced and flexible depending on service requirements by program. The concept of Software-Defined Network (SDN) has a possibility to enable innovation while hiding much of the complexity on the networking design. SDN is mainly used by OpenFlow in real scenario, which can use up to layer-4. In this paper, we propose SDN which consider up to layer-7. To maintain flexible network and to get maximum benefit from networks, Service-oriented Router (SoR) was introduced. A SoR enables layer-2 to layer-7 information to be captured, analyzed, and stored and has a high-throughput database(DB) and is able to analyze all transactions on its interfaces. In addition, SoRs can provide APIs to access stored contents in order to enrich services. In our system, we make network programmable by considering layer-7 information, which can not be captured by using OpenFlow method. This feature will make future SDN more effective and convenient.

Modeling of Router-based Request Redirection for Content Distribution Network

The increase of digital data between content’s servers and clients in a network causes congestion problems when downloading big web contents including files, streaming media, etc. The problem becomes pronounced when a narrow bandwidth or unexpected termination of streaming services is appeared. Content Delivery Network (CDN) is introduced to overcome such problems by redirect client’s request to the best server which proximal and least loaded. However, with intensity increase of people accessing a particular content, the performance of CDN is reduced and sometimes congested. We propose an architecture to solve such problems with a new method to redirect client’s request through a special router called Service-oriented Router (SoR). In this paper, several analytical studies and experiments have been conducted and the result show that router-based redirection is more effective than DNS-based redirection that is currently being used. SoR has been introduces as a content-based router and has capability to do deep packet inspection (DPI) into the packet streams and analyze them. We use SoR in our proposed method as a CDN’s core-router to redirect client’s request to the best server. Our experiment conducted with model and numerical analytic supported by optimal redirection probability based on delay between router and server. The experiment result confirmed that the router-based redirection reduced the response time by 23.3% compared to the DNSbased redirection.

A router-based management system for prediction of network congestion

Network Management System (NMS) plays an important role in networks to maintain the best performance of a network. It employs variety of tools, applications, and devices in order to support network administrators to monitor and maintain the stability of a network. Fault management is part where the NMS dealing with problems and failures, such as congestion, in the network. Generally, most NMSs use Simple Network Management Protocol (SNMP) to monitor and map network availability, performance, and error rates. In the existing NMS process, an SNMP agent is deployed to get information about the network condition and then send them to the administrator for taking further action on solving the problems. However, deploying such agent to the network may increase the traffic density. On the other hand, packet latency and RTT will increase as well. In this paper, we implemented a prototype of the proposing novel system that no need to deploy such agent to obtain network information. Our system analyze the streaming traffic by implementing a Service-oriented Router (SoR). Our objective is to predict a congestion in the specific link in the network through a router-based data traffic analysis using a Bayesian network model. The purpose of the prediction is to support the network administrator to notify the early warning regarding to the fault in the network as long as possible before it actually happening. By this prediction, the network administrator can immediately taking action to avoid the problems.We provided simulation experiment to demonstrate the performance of the proposed system. Our simulation results show that the proposed system can predict a congestion link caused by a particular problem, before hand it is getting congested.

Service-Oriented Router-Based CDN System: An SoR-Based CDN Infrastructure Implementation on a Real Network Environment

Internet users are constantly demanding faster and higher quality services from their internet service providers. Therefore, for fast data delivery of such applications, Content Delivery Networks (CDNs) have been introduced. Most CDN providers use Domain Name Resolution (DNS) based request routing (RR) methods to find the nearest server for a particular client and it has both advantages and disadvantages. Importantly, disadvantages result high latencies of data delivery and network congestions. To maintain rich information in the Internet and to shift the current Internet infrastructure to an information-based open environment platform, Service-oriented Routers (SoRs) have been introduced. An SoR has a high-throughput database and it is able to analyze all transactions on its interfaces. Therefore, we have used the basic functionalities of the SoR to diminish disadvantages of the DNS-based RR methods. Proposed system is independent from DNS-based RR and we have conducted experiments based on content-centric RR using the SoR basic functionalities and successfully evaluated and compared both of the round trip time (RTT) and the packet inter arrival time. Our results indicated that SoR-based method can reduce upto 40-50% latency in both connection initiation time and content migration time in-between servers.

Distributed Algorithm for Router-Based Management of Replica Server in Next-CDN Infrastructure

Extending Content Delivery Network (CDN) infrastructure that has features of router-based network management system (RNMS) is highly appealing and challenging. It allows developing a CDN architecture based upon standard design to ease interoperability, scalability, performance, and flexibility both on network monitoring and management controlled from a router. To better understand the system model, necessity, and the advantages of RNMS, this paper proposed an algorithm that distributed in to a special router called Service-oriented Router (SoR). The function of algorithm is to manage the effective and efficient number of replica server runs in the network. In CDN, minimizing the number of activated replica servers should be considered in order to reduce the operation cost of the system. We propose a semantic approached algorithm that has function to optimize the selection of active replica servers which managed from SoR. The algorithm has capability to find the best location of replica servers and performs load balancing among replica servers. Our simulation result indicates that the proposed algorithm can efficiently activate the replica servers according to users request with 33.9% effective compared to other algorithm within about one millisecond RTT increase.

Evaluation of cache base network processor by using real backbone network trace

In this paper a novel cache-based packet-processing-engine (PPE) architecture that achieves high packet-processing throughput with low-power consumption is proposed and evaluated. As network packets of the same header information appear repeatedly in a short time, a special cache, the so called header-learning cache (HLC), memorizes the packet-processing method and enables most packets to skip the execution at the processing units array. The implementation of the cache-based PPE architecture, P-Gear, was designed. Real backbone network trace was used to evaluate the performance of it. This P-Gear can achieve over 80 % cache hit rate using 4K/32K entry for access/core networks. Compared to conventional PPE, P-Gear can achieve 100-Gbps (gigabit per second) packet-processing throughput with only 36.5% of the die size and 32.6% of the power consumption required by the conventional PPE

Enhanced Patricia Tree with Reordering and Fast Incremental and Decremental Update Functions

 Abstract—Routing-table lookup function is formed as a tree structure. In particular, backbone router of the Internet manages a huge tree structure of the routing table in order to store all routing information brought by routing protocols, such as BGP. Though high-speed lookup is desirable for the backbone router, the tree-based lookup requires multiple memory accesses and it degrades the throughput of the lookup. Aggregation of redundant nodes and elimination of useless nodes are necessary for the high-throughput lookup. Enhanced Patricia Tree (EPT) and Enhanced Patricia Tree with Reordering (EPT-R) were studied for the high-throughput lookup. In this paper, the incremental and decremental update algorithms for EPT-R are proposed and evaluated. These incremental and decremental update algorithms for EPT and EPT-R are effective in quick update time.